This invention relates to new and useful improvements in parts washing machines such as those illustrated in U.S. Pat. No. 3,890,988.
This patent illustrates a parts washing machine which includes a cone shaped primary separator with a pump and motor supported at the apex thereof immediately below the drain from the sink. The secondary intake consists of a tube or conduit extending downwardly through the apex of the support and into the fluid or solvent contained within the tank or container.
Under normal circumstances, this construction operates adequately but if, for example, the pump is left on inadvertently, the fluid level within the container often drops below the intake of the pump inasmuch as the drain cannot return the fluid fast enough to maintain the fluid level.
When this occurs, the pump continues to operate without pumping fluid and overheating can occur. Furthermore, air can be drawn into the pump and an air lock may occur so that even if the pump is switched off and the fluid level is returned to normal, the air lock will often prevent the pump from drawing fluid due to the length of the intake which is occasioned by the design of the primary separator and support cone.
Even although thermal overload means were provided, occasionally the pump motor would burn out due to this overheating and fluid starvation.